Sage 300 P/O Invoice Entry based on Receipt

[itamar lev]

I'm looking for a method to create a P/O Invoice Entry based on a Receipt
using the Sage 300 RESTful API.
At the moment the only way I saw I can create an invoice using the RESTful API is AP/APInvoiceBatches endpoint
however even using this endpoint and in the body setting: "SourceApplication": "PO" it's not what I'm looking for.
Because it does not reference to a receipt. 
Moreover it's not reflected in the response of a GET request to PO/POInvoices endpoint.
And for that endpoint there's no POST/PATCH option.
Thanks,
Itamar